I believe it was Philip Brett who first observed, in his preface to volume 6b of the Byrd Edition (reprinted in William Byrd and his contemporaries: essays and a monograph), that the texts of Byrd's three-part Marian hymns and other extra-liturgical Gradualia pieces are taken from the Little Office of the Blessed Virgin, a book in daily use in recusant Roman Catholic communities in England in post-Reformation times. However, I don’t think it has been previously noted that most of the texts of Byrd's English psalm-settings published in the Psalmes, Songs, and Sonnets of 1611 are also taken from the same source, specifically the parallel Latin–English version first published in 1599 with English translations by Richard Verstegan under the title The Primer, or Office of the Blessed Virgin Marie. Previous commentators, including John Morehen and John Harley, have remarked on the closeness of Byrd's texts to the Douay–Rheims versions, but their relationship to Verstegan's translations is more than just closeness: of Byrd's nine psalm-settings in the 1611 book, five (Come let us rejoice, Sing ye to our Lord, Praise our Lord all ye Gentiles, Make ye joy to God and Arise Lord into thy rest) use Verstegan's texts word-for-word and one (Turn our captivity) merely appends the words ‘with them’ to ‘carrying their sheaves’, presumably to allow Byrd a more extended final point.